Getting all Sweaty

[heorogar]

Hey everyone, I was just curious how to go about doing sweat or tears on a character. Ive noticed a lot of games now such as Heavy Rain or UFC 2009 theres a really awesome effect of the characters being sweaty/wet or crying and it appears to be running down their bodies, and I was curious on how to achieve this. I have a theory that its just a shader effect but i could be wrong. Thanks for your time guys.

P.S
Also one last question for yall. How can I go about making clothes on a character appear to be wrinkling dynamically such as in Uncharted. When nathan drake is moving depending on his torso's position its shows a different set of wrinkles. I know this is with normals maps but would I have to do a different set of wrinkles then plug these different normal maps in a shader ? Im trying to do this in UT3 if that helps. Again thanks for your time guys and gals.

[Cunipshun]

WOW
u have no idea how mind-boggled u just made me and
now that i THINK about it, I think the
blood, sweat, and tears is scripted for game such as UFC and wrestling games etc...

and for wrinkles....IDK

[Mrpearlzildjian]

I'm not real sure, and pretty sure I'll be proven wrong, but in theory, it seems an animated spec map is the most plausible idea I know of the get the sweat. Tears may be just animated single polys or hardware particles from an emitter, depending on how many are needed, what style, etc.

The wrinkles thing is a little more out of my league, but I could see it in the context of the same thing as animated shaders, or maybe they just appear to wrinkle differently based on the stretch of the maps from deformation.

Again, take this with a grain of salt, I'm bound to be proven wrong.

[Maph]

http://ati.amd.com/developer/gdc/2006/GDC06-Advanced_D3D_Tutorial_Day-Tatarchuk-Rain.pdf <- This features a very interesting technique for doing droplets and rain streaks on geometry. Really good read imho.

One (and very straightforward) way to do dynamic wrinkles, would be to design a shader that accepts n number of normal map inputs with a blend/weight factor, and try to link that to deformation (manually, or scripted).
Another way -and I'm just freewheeling here, not sure if this is even possible- is by using dynamic density/tension maps (weight or vertcolor maps) that you can use to blend between normal maps. But at first sight, you probably need an offline solution to calculate the density/tension maps.

There's probably a lot more to tackle this problem though. :think:

[heorogar]

Thanks SOOO much for the information guys! this is definitely sending me on the right track. I am going to try my hand at the animated spec map and Im going to try the creation of a shader. Again thanks for the info guys.


Cunipshun : Sorry for the confusion ;)

[Cunipshun]

Cunipshun : Sorry for the confusion ;)

It's not that i'm confused
just seemed to never noticed or care until now
and now that i care i wanna kno more....
THX Maph

[Ace-Angel]

CE2 has real-time normal mapping changes. Most of the face expressions are 'enhanced' due to this method.

[heorogar]

Ah I see. Unfortunately I cannot play Crysis on my system or at least the Editor . I have the System Specs just the editor refuses to install. Im running Vista 64, intel extreme edition Quad 2.6 ghz and 4 gb ram so i do have the system resources :-/. If i do manage to get the Editor to work ill definitely play with it to see some of the results i get.

I also happen to find this script called kineMapper. Has anyone tried using this ? http://www-viz.tamu.edu/courses/tutorials/gary/index.html
Ill have to give it a try in a little bit. Now the real test is figure out a way to get this into UT3 or in a custom built engine via shader HAH. Again thanks for al the responses guys!

[Ace-Angel]

I stand corrected, UT3 Engine can also do this, however, the ONLY game so far which uses real-time sweating or wrinkles is Legendary: Pandora's Box.

IN other words, a crappy game uses the tech available to it, but doesn't have documentation about it.

[MRico]

Man, change the thread title...I keep thinking there's ganna be like, pictures of hot chicks playing volleyball or something...keep getting my hopes up.

[Buzzy]

I got to see Fight Night Round 4 at E3 and it has some absolutely amazing shader effects. For example, when one of the fighters punches, you can see all of his muscles flex and relax. Very very cool character tech in that game. I'd recommend looking for info about it.